At present, long term evolution (LTE) systems generally adopt intra-frequency networking, and have severe co-channel interference. In practice, a macro diversity gain is obtained by using a method in which multiple RRUs are used to work for one user equipment, for example, multicast or a multi-remote radio unit (RRU) cell, so as to reduce the interference.
When multiple RRUs are used to work for one user equipment, if all RRUs in a cell work for the user equipment, resource utilization is rather low. Therefore, it is necessary to select several effective RRUs to work for the user equipment, that is, select a working RRU for the user equipment. In the prior art, there are mainly two methods for selecting a working RRU for a user equipment. A first method is that, according to reference signal receiving powers (RSRPs) of the user equipment received by all RRUs in a cell, RSRPs are sorted in descending order, and RRUs corresponding to the first N RSRPs are selected as working RRUs of the user equipment. A second method is that, according to RSRPs of the user equipment received by all RRUs in a cell, the RSRPs are sorted in descending order, and RRUs corresponding to N RSRPs, differences between which and a first RSRP are within a certain threshold, are selected as working RRUs of the user equipment. The foregoing two methods in the prior art both cannot achieve a good balance between resource utilization and interference cancellation, and cannot accurately determine a working RRU of a user equipment.